Method for making indene

Abstract

Unsubstituted and substituted bicyclic indene precursors more saturated than indene are converted to indene by a dehydrogenation process in which the indene precursor in the presence of an oxygen donor is contacted with a phosphate catalyst.

We claim: 
     
       1. A dehydrogenation process for producing unsubstituted or substituted indene from an unsubstituted or substituted bicyclic indene precursor more saturated than indene, said substituted indene precursor being substituted with at least one of C 1  -C 4  alkyl, C 1  -C 4  alkenyl and phenyl, said process comprising contacting said indene precursor and an oxygen donor with a phosphate catalyst represented by the formula:   M.sub.a P.sub.x O.sub.y     wherein   M is one or more elements selected from the group consisting of Mg, Sr, Ca, Ba, La, Ce, other rare earths, Cr, Mn, Co, Ni, Cu, Zn, Pb, Bi, Te, B, Al, Rh, Sb, As, Ge, U, Th and Ru; and wherein     0.1 × ≦ a ≦ 10x, wherein a represents the sum of subscript a of all of the metal ions and y is a number such that the valence requirements of the metal ions for oxygen is satisfied.   
     
     
       2. The process of claim 1 wherein the reaction temperature of said process is at least 100° C. 
     
     
       3. The process of claim 2 wherein said indene precursor is selected from the group consisting of indane, alkyl indanes in which the alkyl groups have from 1 to 4 carbon atoms, tetrahydroindene, alkyl tetrahydroindenes in which the alkyl groups have from 1 to 4 carbon atoms, hexahydroindene, hexahydroindane and vinyl norbornene. 
     
     
       4. The process of claim 1 wherein said oxygen donor is O 2 . 
     
     
       5. The process of claim 4 wherein said reaction temperature is 100° to 650° C. 
     
     
       6. The process of claim 5 wherein said reaction temperature is 250° to 550° C. 
     
     
       7. The process of claim 1 wherein said phosphate catalyst consists essentially of a composition represented by the formula:   M.sub.a P.sub.x O.sub.y     wherein   M is one or more elements selected from the group consisting of Mg, Sr, Ca, Ba, La, Ce, other rare earths, Cr, Mn, Co, Ni, Cu, Zn, Pb, Bi, Te, B, Al, Rh, Sb, As, Ge, U, Th and Ru; and wherein     
     
     
       0. 1 × ≦ a ≦ 10x; wherein a represents the sum of subscripts a of all of the metal ions and y is a number such that the valence requirements of the metal ions for oxygen is satisfied. 
     
     
       8. The process of claim 3 wherein said phosphate catalyst consists essentially of a composition characterized by the formula:   M'.sub.b M.sub.a P.sub.x O.sub.y     wherein   M is at least one of Bi, Ni, Co, Cr, La, Mg, Ca, Ce, U, Sb; wherein     M' is at least one element selected from the group consisting of Ge, Pb, Mo. W, Sr, Be, Re, Th, As, Te, and elements selected from Groups IB, IIB, IA, IIIA, and VB of the Periodic Table; and wherein     0.1 ≦ a ≦ 16, 0 ≦ b ≦ 16, 0.5 ≦ x ≦ 16 and y is a number such that the valence requirements of the remaining elements for oxygen are satisfied.   
     
     
       9. The process of claim 8 wherein said phosphate catalyst contains at least one of Bi, Sn, Co, Cr, La, Sn, Mg, U and Sb, and further wherein said catalyst contains at least one of Mo, W and Ti. 
     
     
       10. The process of claim 3 wherein said catalyst is selected from the group consisting of Co 12  P 12  O y , Mg 9  CrBiP 12 .5 O y , Mg 9  CrBiW 0 .5 P 12 .5 O y , Mg 9  CrBiMo 0 .5 P 12  O y , K 0 .01 Co 9  LaBiP 12  O y , Co 10  Cd 2  P 12  O y , Cd 12  P 12  O y , K 0 .1 Co 9  CrBiP 12  O y , Cs 0 .02 Co 9  LaBiP 12  O y , Co 10  SbP 12  O y  and K 0 .5 Co 9  LaBiP 12  O y . 
     
     
       11. The process of claim 3 wherein said indene precursor is so selected that indene is produced by said process. 
     
     
       12. The process of claim 3 wherein said phosphate catalyst consists essentially of a composition characterized by the formula:   M.sub.a X.sub.b Bi.sub.l P.sub.x O.sub.y     wherein   M is one or more elements selected from the group consisting of Mg, Ca, Co, Ba, Sr, Mn (II), Ni, Cu, Zn and Pb; wherein     X is at least one of La, Cr, Ce, other rare earths, B, Al, Ru and Rh; and wherein     0 ≦ a + b ≦ 10x and 0.5 ≦ x ≦ 100, and wherein a + b represents the sum of all subscripts a and all subscripts b and y is a number such that the valence requirements of the other elements for oxygen is satisfied.